In this context, ultrawideband microwave radar technology is an attractive alternative. The general approach is to illuminate the breast with a UWB pulse from a number of antenna locations. The backscattered waves are collected and post-processed to obtain a high resolution dielectric map of the breast. This approach relies on the contrast between the dielectric properties of normal and malignant tissues at microwave frequencies. The intrinsic contrast is estimated to vary from a minimum of 2:1 to a maximum of 10:1, whereas for X-ray is only a few percent.
Based on these considerations, we investigate the design of a low cost CMOS integrated circuit that can be connected to an array of antennas to perform monostatic or bistatic measurements. Each IC acts as a transceiver, generating stepped frequency waveforms and collecting back the scattered signals from the breast. By means of inverse Fourier transform time-domain waveforms are obtained. From the waveform and the time of flight of the back scattered pulses it is possible to derive information on the reflecting objects, such that their distance and size.